title: Brain Gray Matter Deficits in Patients with Chronic Primary Insomnia.
abstract: OBJECTIVE
  To investigate the structural changes in patients with chronic primary insomnia and the relationships with clinical features of insomnia.
  
  
  METHODS
  Statistical parametric mapping 8-based voxel-based morphometry was used to identify differences in regional gray and white matter between patients with chronic primary insomnia and normal controls.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  Twenty-seven patients and 27 age/sex-matched controls.
  
  
  METHODS
  Regional differences were compared using two-samplet-tests with age, sex, and intracranial volume as covariates.
  
  
  RESULTS
  The patients were a mean age of 52.3 y and had a mean history of insomnia of 7.6 y. Patients displayed cognitive deficits in attention, frontal/executive function, and nonverbal memory. Patients also displayed significantly reduced gray matter concentrations (GMCs) in dorsolateral prefrontal and pericentral cortices, superior temporal gyrus, and cerebellum and decreased gray matter volumes in medial frontal and middle temporal gyri compared with control patients with the cluster threshold ≥ 50 voxels at the level of uncorrected P < 0.001. Negative correlations were found between GMC of the prefrontal cortex and insomnia severity and the wakefulness after sleep onset, and between GMC of pericentral cortex and sleep latencies. None of the findings continued to be significant after correction for multiple comparisons.
  
  
  CONCLUSIONS
  We found gray matter deficits in multiple brain regions including bilateral frontal lobes in patients with psychophysiologic insomnia. Gray matter deficit of the pericentral and lateral temporal areas may be associated with the difficulties in sleep initiation and maintenance. It is still unclear whether gray matter reductions are a preexisting abnormality or a consequence of insomnia.
  
  
  BACKGROUND
  Joo EY; Noh HJ; Kim JS; Koo DL; Kim D; Hwang KJ; Kim JY; Kim ST; Kim MR; Hong SB. Brain gray matter deficits in patients with chronic primary insomnia.SLEEP2013;36(7):999-1007.
authors.affiliation: Department of Neurology, Samsung Medical Center, Samsung Biomedical Research Institute; Sungkyunkwan University School of Medicine, Seoul South Korea.
authors.forename: Eun Yeon
authors.initials: EY
authors.lastname: Joo
authors.forename: Hyun Jin
authors.initials: HJ
authors.lastname: Noh
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Kim
authors.forename: Dae Lim
authors.initials: DL
authors.lastname: Koo
authors.forename: Daeyoung
authors.initials: D
authors.lastname: Kim
authors.forename: Kyoung Jin
authors.initials: KJ
authors.lastname: Hwang
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Sung Tae
authors.initials: ST
authors.lastname: Kim
authors.forename: Mi Rim
authors.initials: MR
authors.lastname: Kim
authors.forename: Seung Bong
authors.initials: SB
authors.lastname: Hong
keywords: Brain; gray matter concentration; insomnia; voxel-based morphometry